One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(3,7)(9,10,15,16)(11,12,13,14)(19,23)(21,24)(25,26)(27,33)(28,32)(29,30)(31,34)(35,39)(36,37)(38,40)(2,4)(6,8)(9,11,15,13)(10,12,16,14)(26,30)(27,34)(32,36)(35,40)(1,2,5,4)(3,8,7,6)(9,12,15,14)(10,11,16,13)(17,18,20,22)(19,21,23,24)(25,26)(27,33)(28,36)(29,30)(31,34)(32,37)(35,38)(39,40)(1,3,5,7)(2,6,4,8)(9,13,15,11)(10,12,16,14)(17,19)(18,21)(20,23)(22,24)(25,27)(26,31)(28,35)(29,34)(30,33)(32,38)(36,39)(37,40)(1,4,5,2)(3,8,7,6)(9,14,15,12)(10,11,16,13)(25,28,29,37)(26,32,30,36)(27,35,34,40)(31,38,33,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.